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P. H. ZIMMER. ELECTROMAGNEUC SWlTCH. APPLICATION man AFILZS. 1914,.

Patented June 17; 1919.

UNITED STATES PATENT OFFICE.

PAUL H. ZIMMER, 0F MILWAUKEE, WISCONSIN, ASSIGNOR TO THE CUTLER-HAMMER MFG. CO., OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

ELE-C TRJOMAGNETIC SWITCH.

Specification of Letters Patent.

Patented J 11110 1'7, 1919.

Application filed April 23, 1914. Serial No. 833,965.

T 0 all whom it may concern Be it known that I, PAUL H. ZIMMER, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of \Visconsin, have invented new and useful Improvements in Electromagnetic Switches, of which the following is a full, clear, concise, and exact description, refer ence being had to the accompanying drawing, forming a part of this specification.

This invention. relates to improvements in electromagnetic switches.

It has among its objects to provide an improved elcctromagnetie switch of the type wherein the switch member is mechaiiically locked in attracted position to permit deenergization of its operating winding and wherein such locking means is tripped upon subsequent cnergization of the operating winding.

The more specific objects of the invention will appear in connection with the embodiment thereof illustrated in the accompanying drawing, it being understood that various modifications may be made in the structure illustrated without departure from the scope of the invention.

In the drawing.

Figure 1 is a side elevation of the switch in open position and provided with certain circuit connections;

Fig. 2 is a similar view of the switch in closed position but with certain parts removed and other parts shown in section; and,

Figs. 3 and 4 are detail views of a control switch for the operating magnet.

The switch includes a stationary contact 1, a cooperating movable contact 2, an elec tromagnet 3 and an armature member 1 for said magnet carrying the contact 2. The arrangement of parts is such that when the magnet is energized it attracts its armature 4 to move the contact 2 into engagement with contact 1. On the other hand, when the magnet is deeinergized its armature tends to gravitate to the position illustrated, thereby separating the switch contacts. F urther, a spring 5 associated in a well-known manner with the armature 4 and movable contact 2 serves to supplement the action of gravity in effecting the return of the armature and accordingly of the switch contact 2 to normal position. A latch 6 is provided to mechant cally lock the armature 4 in attracted position to maintain the switch contacts in engagement and the magnet is provided with an auxiliary armature 7 to trip said latch as hereinafter set forth to effect release of the armature l. A doublethrow switch 8 is provided to be thrown in one direction by the armature 4 and in an opposite direction by the auxiliary armature T to elfect automatic control of the circuit of the magnet 3. As hereinafter more specifically set forth. the switch h effects decnergization of the mag not upon attraction of the armature l and also upon attraction of the auxiliary armature 7.

More specifically describing the structure illustrated. the several parts thereof are mounted upon a suitable insulating panel or base 9. The magnet winding is arranged upon a core 10 fixed to the upright portion of an. L-shaped magnet frame 11 suitably secured to the panel 9. The armature is pivotally connected by a pin 12, to the outer end of the horizontal portion of the magnet frame 11 and the auxiliary armature T is pivotally connected. by a pin 13. to the upper end of the vertical member of the magnet frame. The armatures l and T are so pro portioned and arranged that when the armature t is in attracted position and said auxiliary armature is attracted the latter will abut the extremity of the former. The auxiliary armature is, however biased up wardly by a spring 1st connected to an adjustable device 15 on the panel 9, and this spring is so tensioned as to hold the auxiliary armature against attraction until the armature 4 is first attracted. In other words. the two armatnres are so arranged in the magnetic field that the. auxiliary armature will be unresponsive until the armature l is attracted to increase the magnetic flux through said auxiliary armature to a degree sufficient to effect its attraction.

The latch 6 as best illustrated is pivoted on the pin 13 and is biased upwardly by a spring 16 seated in the magnet frame and bearing against a shoulder on said latch. The free end of said latch cooperates with a roller 17 carried by the armature 4 and is Provided with a notch IS, to receive said roller, and thus lock said armature in attracted position. The cooperation of the latch and roller is rendered automatic by the beveled extremity 19 of said latch.

The latch 6, as aforesaid, is adapted to bc tripped by attraction oi the auxiliary armature T. As shown in Fig. 2, the an iliary armature and the latch are pivoted upon the same pin and the former recessed to receive the latter. Thus the armature has a portion 2t) overlying said latch to strike and trip the same when said ar1nature is attracted.

From the foregoing it will be apparent that when the magnet 3 is energized it will attra t its armature and thereby move the contact 2 in engagement with contact 1 while the armature 4 will be locked by the latch 6. Ilence if the magnet is immedi ately deenergized before attracting its auxiliary armature the switch will remain locked in closed position. Then it the magnet is again energized it will attract its auxiliary armature and trip the latch. This in turn mechanically releases the armature at so that upon deencrgimltion of the magnet said armature will return to normal position.

The switch 8 automatically effects the dci nergiaation of the magnet under the conditions just described. This switch coniprises stationary contacts 21 and 22 mounted upon the panel 9 and a double throw contact 23 movable therehetween. As best illustrated in Figs. 3 and 1 the contact 23 is carried by an angular arm 2-1 pivoted at 25 to one end of a hollow bell crank arm 26. The arm 26 in turn is pivoted at 27 to a supporting post 28 projecting outwardly from he panel .3. Adjacent to the piiotal connection between the two arms 21 and 26 the latter is provided with an insulating lug 22 to be engaged by the armature l and on the pivot pin of the member 26 is provided a coil spring 30 having one end bearing against the under side of the post 8 and its other end bearing against a pin 31 provided upon the arm 24, above its pivot 25. The spring 30 thus tends to hold the two arms 24 and 26 in such relation that the former abuts against the iatter at a point 33 and further tends to bias both arms downwardly whereby the contact 23 is normally pressed against the down contact 22. On the other hand, when the armature 4 strikes the lug 29 it rocks the arm 26 against the action of the spring 30 and said spring in turn. by its engagement with the pin 31 on the arm 24, causes said latter arm to move with the arm 26 until the contact 23 strikes the up contact 21. Then the spring 30 permits continued movement of the arm 26,

thereby increasing the spring pressure onof an insulated lug 34 projecting laterally therefrom to overlie said member 24.

Thus it will be observed that the contact 23 normally stands in engagement with the down contact 22 under pressure of the spring 30, that when the arn'iaturc 4 is at tractcd it operates the arm 26 as aforesaid to throw the contact 23 into engagement with the up contact 21 and that when the auxiliary armature 7 is attracted it strikes the arm 24- moving the contact 23 out of engagement with the up contact 21. Then when the armature 4- is released the arm 26 is likewise released and under the influence of the spring 30 and through its engagement with the arm 24, restores the contact 23 to engagement with down contact 22. Further, it will be observed that due to the connection of the arms 24 and 2t). eccentrically to the pivot of the latter, the arm 24 will. in operation, receive a rccipror able, as well as oscillatory. movement. thereby providing for a wiping engagement between the conlact 23 and its cooperating contacts. The advantages of this wiping contact will be readily apparent.

Refcrrin now to the circuit connections shown in Flg. 1, the magnet has one terminal connected. directly to one side of a supply circuit L, L and has its opposite terminal connected to a binding post 28 provided on the support 28 of the switch arm 8 whereby said. magnet is electrically connected to said switch arm. The contacts 21 and 22 are connected through binding posts 21 and 22 respectively to contacts 3 and s respectively which are adapted to be selectively connected to line L by a switch arm S. Thus with the parts positioned as shown in Fig. 1, engagement of the switch arm 8 with con tact s will complete the circuit of the magnet through switch arm 8 and contact 22. The magnet will then attract the armature 4, moving the contact 2 into engagement with contact 1 and substantially simultaneously opening the control switch 8 at contact points 22 an 23 before the auxiliary armature 7 has an opportunity to respond. Also, simultaneously with the engagement of the switch contacts 1 and 2 the latch 6 will lock the armature to retain the same in attracted position when the magnet is deenergized, as aforesaid. The parts will then remain in the positions described until the magnet is again energized and due to the fact that the contacts 22 and 23 are separated the magnet can onl be energized by shifting the switch arm from contact 8 to contact 8. This will complete an energizing circuit for the magnet through contacts 23 and 21, whereupon the magnet will attract the auxiliary armature 7 thereby tripping the latch 6 and at the same time moving contact 23 out of enga ement with contact 21. This will again e ect deenergization of the magnet thus causing it to release both armatures 4 and 7 with the result of restoring the parts to the positions illustrated in Fig. 1.

It will, of course, be understood that the switch arm S and its cooperating contacts n'ierely represent one of numerous control instrunientalities which might be employed to control the parallel circuits of the magnet.

\Vhat I claim as new and desire to secure by Letters Patent is:

1. In combination, a switch element, mechanical means for latching the same in a certain position, an electromagnet, a member to be attracted by said electromagnet to move said switch element to said position, a second member to be attracted by said electron'lagnet to trip said latching means to release said switch element, the former member constituting controlling means for the magnetic circuit of said second member to insure attraction of said members progressively and means to energize and deenergize said electromagnet.

2. In combination, a switch element, mechanical means to latch said element in a certain. position, an clectromagnet, a member to be attracted by said electroi'nagnet to move said switch element to said position, a second member to be attracted by said electromagnet to trip said latching means for release of said switch element, said second member having its magnetic circuit subjected to control by the former member to delay its attraction until after attraction of said former member and control means to deenergize said electromagnet automatically upon movement of said switch element to said certain position.

3. In combination, a switch element, me.- chanical means to latch said element in a certain position, an electromagnet, a memher to be attracted by said electromagnet to more said switch element to said position, a second member to be attracted by said electromagnet to trip said latching means for release of said switch element, said second member having its magnetic circuit subjected to control by the former member to delay its attraction until after attraction of said former member and control means to deenergize said electromagnet automatically upon movement of said switch element to said certain position and also upon tripping of said latching means by said second member.

4. In combination, a switch element, me chanical means to latch said element in a certain position, an electromagnet, a memher to be attracted by said electromagnet to move said switch element to said position, a second member to be attracted by said electromagnet to trip said latching means for release of said switch element, said second member having its magnetic circuit subjected to control by the former member to delay its attraction until after attraction of said former member and a double throw control switch for said electromagnet operable by certain of the aforesaid parts to insure deenergization of said electromagnet immediately upon latching and unlatching of said switch element.

5. In combination, an electromagnetic winding, a main armature, therefor, mechanical means for latching said armature in attracted position, an auxiliary armature for said winding adapted when attracted to trip said latching means, said auxiliary armature having its magnetic circuit extending through said main armature to render its attraction dependent upon prior attraction of said main armature and means actuated by said armatures to effect deenergization of said winding substantially simultaneously with the completion of movement of each of said armatures.

6. In combination, an electromagnetic winding, a main armature therefor, nechanical means for latching said armature in attracted position, an auxiliary armature for said winding adapted when attracted to trip said latching means, said auxiliary armature having its magnetic circuit extending through said main armature to render its attraction dependent upon prior attraction of said main armature and a double throw control switch for said winding operable in one direction by said main armature upon full movement thereof to deenergizc said winding and operable in an oppo site direction by said auxiliary armature upon full movement thereof to deiinergize said winding.

7. In combination, an electromagnetic winding, a main armature therefor, mechanical means to latch said armature in attracted position, an auxiliary armature for said winding adapted to be attracted thereby to trip said latching means, said auxiliary armature having attraction resistive means and having its magnetic circuit extending through said main armature to render its attraction dependent upon prior attraction of said main armature and means to energize and deenergize said winding to set and trip said main armature.

In Witness whereof, I. have hereunto subscribed my name in the presence of two wit nesses.

PAUL H. ZIMMER. Witnesses:

TEKLA BAST, L. A. WATSON.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, D. G. 

